// Copyright 2014 Citra Emulator Project / PPSSPP Project
// Licensed under GPLv2 or any later version
// Refer to the license.txt file included.
#include <algorithm>
#include <cinttypes>
#include <list>
#include <vector>
#include "common/assert.h"
#include "common/common_types.h"
#include "common/logging/log.h"
#include "common/math_util.h"
#include "common/thread_queue_list.h"
#include "core/arm/arm_interface.h"
#include "core/core.h"
#include "core/core_timing.h"
#include "core/hle/kernel/errors.h"
#include "core/hle/kernel/handle_table.h"
#include "core/hle/kernel/kernel.h"
#include "core/hle/kernel/memory.h"
#include "core/hle/kernel/mutex.h"
#include "core/hle/kernel/process.h"
#include "core/hle/kernel/thread.h"
#include "core/hle/result.h"
#include "core/memory.h"
namespace Kernel {
/// Event type for the thread wake up event
static CoreTiming::EventType* ThreadWakeupEventType = nullptr;
bool Thread::ShouldWait(Thread* thread) const {
return status != THREADSTATUS_DEAD;
}
void Thread::Acquire(Thread* thread) {
ASSERT_MSG(!ShouldWait(thread), "object unavailable!");
}
// TODO(yuriks): This can be removed if Thread objects are explicitly pooled in the future, allowing
// us to simply use a pool index or similar.
static Kernel::HandleTable wakeup_callback_handle_table;
// The first available thread id at startup
static u32 next_thread_id;
/**
* Creates a new thread ID
* @return The new thread ID
*/
inline static u32 const NewThreadId() {
return next_thread_id++;
}
Thread::Thread() {}
Thread::~Thread() {}
/**
* Check if the specified thread is waiting on the specified address to be arbitrated
* @param thread The thread to test
* @param wait_address The address to test against
* @return True if the thread is waiting, false otherwise
*/
static bool CheckWait_AddressArbiter(const Thread* thread, VAddr wait_address) {
return thread->status == THREADSTATUS_WAIT_ARB && wait_address == thread->wait_address;
}
void Thread::Stop() {
// Cancel any outstanding wakeup events for this thread
CoreTiming::UnscheduleEvent(ThreadWakeupEventType, callback_handle);
wakeup_callback_handle_table.Close(callback_handle);
callback_handle = 0;
// Clean up thread from ready queue
// This is only needed when the thread is termintated forcefully (SVC TerminateProcess)
if (status == THREADSTATUS_READY) {
Core::System::GetInstance().Scheduler().UnscheduleThread(this, current_priority);
}
status = THREADSTATUS_DEAD;
WakeupAllWaitingThreads();
// Clean up any dangling references in objects that this thread was waiting for
for (auto& wait_object : wait_objects) {
wait_object->RemoveWaitingThread(this);
}
wait_objects.clear();
// Release all the mutexes that this thread holds
ReleaseThreadMutexes(this);
// Mark the TLS slot in the thread's page as free.
u64 tls_page = (tls_address - Memory::TLS_AREA_VADDR) / Memory::PAGE_SIZE;
u64 tls_slot =
((tls_address - Memory::TLS_AREA_VADDR) % Memory::PAGE_SIZE) / Memory::TLS_ENTRY_SIZE;
Core::CurrentProcess()->tls_slots[tls_page].reset(tls_slot);
}
void WaitCurrentThread_Sleep() {
Thread* thread = GetCurrentThread();
thread->status = THREADSTATUS_WAIT_SLEEP;
}
void WaitCurrentThread_ArbitrateAddress(VAddr wait_address) {
Thread* thread = GetCurrentThread();
thread->wait_address = wait_address;
thread->status = THREADSTATUS_WAIT_ARB;
}
void ExitCurrentThread() {
Thread* thread = GetCurrentThread();
thread->Stop();
Core::System::GetInstance().Scheduler().RemoveThread(thread);
}
/**
* Callback that will wake up the thread it was scheduled for
* @param thread_handle The handle of the thread that's been awoken
* @param cycles_late The number of CPU cycles that have passed since the desired wakeup time
*/
static void ThreadWakeupCallback(u64 thread_handle, int cycles_late) {
SharedPtr<Thread> thread = wakeup_callback_handle_table.Get<Thread>((Handle)thread_handle);
if (thread == nullptr) {
LOG_CRITICAL(Kernel, "Callback fired for invalid thread %08X", (Handle)thread_handle);
return;
}
bool resume = true;
if (thread->status == THREADSTATUS_WAIT_SYNCH_ANY ||
thread->status == THREADSTATUS_WAIT_SYNCH_ALL || thread->status == THREADSTATUS_WAIT_ARB) {
// Remove the thread from each of its waiting objects' waitlists
for (auto& object : thread->wait_objects)
object->RemoveWaitingThread(thread.get());
thread->wait_objects.clear();
// Invoke the wakeup callback before clearing the wait objects
if (thread->wakeup_callback)
resume = thread->wakeup_callback(ThreadWakeupReason::Timeout, thread, nullptr, 0);
}
if (resume)
thread->ResumeFromWait();
}
void Thread::WakeAfterDelay(s64 nanoseconds) {
// Don't schedule a wakeup if the thread wants to wait forever
if (nanoseconds == -1)
return;
CoreTiming::ScheduleEvent(nsToCycles(nanoseconds), ThreadWakeupEventType, callback_handle);
}
void Thread::CancelWakeupTimer() {
CoreTiming::UnscheduleEvent(ThreadWakeupEventType, callback_handle);
}
void Thread::ResumeFromWait() {
ASSERT_MSG(wait_objects.empty(), "Thread is waking up while waiting for objects");
switch (status) {
case THREADSTATUS_WAIT_SYNCH_ALL:
case THREADSTATUS_WAIT_SYNCH_ANY:
case THREADSTATUS_WAIT_ARB:
case THREADSTATUS_WAIT_SLEEP:
case THREADSTATUS_WAIT_IPC:
break;
case THREADSTATUS_READY:
// The thread's wakeup callback must have already been cleared when the thread was first
// awoken.
ASSERT(wakeup_callback == nullptr);
// If the thread is waiting on multiple wait objects, it might be awoken more than once
// before actually resuming. We can ignore subsequent wakeups if the thread status has
// already been set to THREADSTATUS_READY.
return;
case THREADSTATUS_RUNNING:
DEBUG_ASSERT_MSG(false, "Thread with object id %u has already resumed.", GetObjectId());
return;
case THREADSTATUS_DEAD:
// This should never happen, as threads must complete before being stopped.
DEBUG_ASSERT_MSG(false, "Thread with object id %u cannot be resumed because it's DEAD.",
GetObjectId());
return;
}
wakeup_callback = nullptr;
status = THREADSTATUS_READY;
Core::System::GetInstance().Scheduler().ScheduleThread(this, current_priority);
Core::System::GetInstance().PrepareReschedule();
}
/**
* Finds a free location for the TLS section of a thread.
* @param tls_slots The TLS page array of the thread's owner process.
* Returns a tuple of (page, slot, alloc_needed) where:
* page: The index of the first allocated TLS page that has free slots.
* slot: The index of the first free slot in the indicated page.
* alloc_needed: Whether there's a need to allocate a new TLS page (All pages are full).
*/
std::tuple<u32, u32, bool> GetFreeThreadLocalSlot(std::vector<std::bitset<8>>& tls_slots) {
// Iterate over all the allocated pages, and try to find one where not all slots are used.
for (unsigned page = 0; page < tls_slots.size(); ++page) {
const auto& page_tls_slots = tls_slots[page];
if (!page_tls_slots.all()) {
// We found a page with at least one free slot, find which slot it is
for (unsigned slot = 0; slot < page_tls_slots.size(); ++slot) {
if (!page_tls_slots.test(slot)) {
return std::make_tuple(page, slot, false);
}
}
}
}
return std::make_tuple(0, 0, true);
}
/**
* Resets a thread context, making it ready to be scheduled and run by the CPU
* @param context Thread context to reset
* @param stack_top Address of the top of the stack
* @param entry_point Address of entry point for execution
* @param arg User argument for thread
*/
static void ResetThreadContext(ARM_Interface::ThreadContext& context, VAddr stack_top,
VAddr entry_point, u64 arg) {
memset(&context, 0, sizeof(ARM_Interface::ThreadContext));
context.cpu_registers[0] = arg;
context.pc = entry_point;
context.sp = stack_top;
context.cpsr = 0;
context.fpscr = 0;
}
ResultVal<SharedPtr<Thread>> Thread::Create(std::string name, VAddr entry_point, u32 priority,
u64 arg, s32 processor_id, VAddr stack_top,
SharedPtr<Process> owner_process) {
// Check if priority is in ranged. Lowest priority -> highest priority id.
if (priority > THREADPRIO_LOWEST) {
LOG_ERROR(Kernel_SVC, "Invalid thread priority: %u", priority);
return ERR_OUT_OF_RANGE;
}
if (processor_id > THREADPROCESSORID_MAX) {
LOG_ERROR(Kernel_SVC, "Invalid processor id: %d", processor_id);
return ERR_OUT_OF_RANGE_KERNEL;
}
// TODO(yuriks): Other checks, returning 0xD9001BEA
if (!Memory::IsValidVirtualAddress(*owner_process, entry_point)) {
LOG_ERROR(Kernel_SVC, "(name=%s): invalid entry %016" PRIx64, name.c_str(), entry_point);
// TODO (bunnei): Find the correct error code to use here
return ResultCode(-1);
}
SharedPtr<Thread> thread(new Thread);
Core::System::GetInstance().Scheduler().AddThread(thread, priority);
thread->thread_id = NewThreadId();
thread->status = THREADSTATUS_DORMANT;
thread->entry_point = entry_point;
thread->stack_top = stack_top;
thread->nominal_priority = thread->current_priority = priority;
thread->last_running_ticks = CoreTiming::GetTicks();
thread->processor_id = processor_id;
thread->wait_objects.clear();
thread->wait_address = 0;
thread->name = std::move(name);
thread->callback_handle = wakeup_callback_handle_table.Create(thread).Unwrap();
thread->owner_process = owner_process;
// Find the next available TLS index, and mark it as used
auto& tls_slots = owner_process->tls_slots;
bool needs_allocation = true;
u32 available_page; // Which allocated page has free space
u32 available_slot; // Which slot within the page is free
std::tie(available_page, available_slot, needs_allocation) = GetFreeThreadLocalSlot(tls_slots);
if (needs_allocation) {
// There are no already-allocated pages with free slots, lets allocate a new one.
// TLS pages are allocated from the BASE region in the linear heap.
MemoryRegionInfo* memory_region = GetMemoryRegion(MemoryRegion::BASE);
auto& linheap_memory = memory_region->linear_heap_memory;
if (linheap_memory->size() + Memory::PAGE_SIZE > memory_region->size) {
LOG_ERROR(Kernel_SVC,
"Not enough space in region to allocate a new TLS page for thread");
return ERR_OUT_OF_MEMORY;
}
size_t offset = linheap_memory->size();
// Allocate some memory from the end of the linear heap for this region.
linheap_memory->insert(linheap_memory->end(), Memory::PAGE_SIZE, 0);
memory_region->used += Memory::PAGE_SIZE;
owner_process->linear_heap_used += Memory::PAGE_SIZE;
tls_slots.emplace_back(0); // The page is completely available at the start
available_page = static_cast<u32>(tls_slots.size() - 1);
available_slot = 0; // Use the first slot in the new page
auto& vm_manager = owner_process->vm_manager;
vm_manager.RefreshMemoryBlockMappings(linheap_memory.get());
// Map the page to the current process' address space.
// TODO(Subv): Find the correct MemoryState for this region.
vm_manager.MapMemoryBlock(Memory::TLS_AREA_VADDR + available_page * Memory::PAGE_SIZE,
linheap_memory, offset, Memory::PAGE_SIZE,
MemoryState::ThreadLocal);
}
// Mark the slot as used
tls_slots[available_page].set(available_slot);
thread->tls_address = Memory::TLS_AREA_VADDR + available_page * Memory::PAGE_SIZE +
available_slot * Memory::TLS_ENTRY_SIZE;
// TODO(peachum): move to ScheduleThread() when scheduler is added so selected core is used
// to initialize the context
ResetThreadContext(thread->context, stack_top, entry_point, arg);
return MakeResult<SharedPtr<Thread>>(std::move(thread));
}
void Thread::SetPriority(u32 priority) {
ASSERT_MSG(priority <= THREADPRIO_LOWEST && priority >= THREADPRIO_HIGHEST,
"Invalid priority value.");
Core::System::GetInstance().Scheduler().SetThreadPriority(this, priority);
nominal_priority = current_priority = priority;
}
void Thread::UpdatePriority() {
u32 best_priority = nominal_priority;
for (auto& mutex : held_mutexes) {
if (mutex->priority < best_priority)
best_priority = mutex->priority;
}
BoostPriority(best_priority);
}
void Thread::BoostPriority(u32 priority) {
Core::System::GetInstance().Scheduler().SetThreadPriority(this, priority);
current_priority = priority;
}
SharedPtr<Thread> SetupMainThread(VAddr entry_point, u32 priority,
SharedPtr<Process> owner_process) {
// Setup page table so we can write to memory
SetCurrentPageTable(&Core::CurrentProcess()->vm_manager.page_table);
// Initialize new "main" thread
auto thread_res = Thread::Create("main", entry_point, priority, 0, THREADPROCESSORID_0,
Memory::HEAP_VADDR_END, owner_process);
SharedPtr<Thread> thread = std::move(thread_res).Unwrap();
// Register 1 must be a handle to the main thread
thread->guest_handle = Kernel::g_handle_table.Create(thread).Unwrap();
thread->context.cpu_registers[1] = thread->guest_handle;
// Threads by default are dormant, wake up the main thread so it runs when the scheduler fires
thread->ResumeFromWait();
return thread;
}
void Thread::SetWaitSynchronizationResult(ResultCode result) {
context.cpu_registers[0] = result.raw;
}
void Thread::SetWaitSynchronizationOutput(s32 output) {
context.cpu_registers[1] = output;
}
s32 Thread::GetWaitObjectIndex(WaitObject* object) const {
ASSERT_MSG(!wait_objects.empty(), "Thread is not waiting for anything");
auto match = std::find(wait_objects.rbegin(), wait_objects.rend(), object);
return static_cast<s32>(std::distance(match, wait_objects.rend()) - 1);
}
VAddr Thread::GetCommandBufferAddress() const {
// Offset from the start of TLS at which the IPC command buffer begins.
static constexpr int CommandHeaderOffset = 0x80;
return GetTLSAddress() + CommandHeaderOffset;
}
////////////////////////////////////////////////////////////////////////////////////////////////////
/**
* Gets the current thread
*/
Thread* GetCurrentThread() {
return Core::System::GetInstance().Scheduler().GetCurrentThread();
}
void ThreadingInit() {
ThreadWakeupEventType = CoreTiming::RegisterEvent("ThreadWakeupCallback", ThreadWakeupCallback);
next_thread_id = 1;
}
void ThreadingShutdown() {
Kernel::ClearProcessList();
}
} // namespace Kernel